As an exhaust gas analyzing system of this kind, there is one adapted to measure carbon monoxide (CO), total hydrocarbons (THC), nitrogen oxides (NOX), carbon dioxide (CO2) and the like contained, for example, in engine exhaust gas exhausted from an engine of an automobile.
Specifically, the exhaust gas analyzing system mentioned above includes an exhaust gas flow line for rendering engine exhaust gas to flow therethrough and an exhaust gas analyzing device provided in the exhaust gas flow line to measure the various kinds of components mentioned above contained in the exhaust gas flowing through the corresponding exhaust gas flow line.
Then, in the exhaust gas analyzing system mentioned above, at the time of product shipment of the exhaust gas analyzing device, initial setting data indicating types of gas analyzers contained in the corresponding exhaust gas analyzing device and initial setting values such as calculation factor information such as a calibration curve factor, calibration factor and the like of each of the gas analyzers is recorded in an external recording medium such as a CD-R so as to be appended to the exhaust gas analyzing device. Then, it is necessary to perform regular maintenance for the exhaust gas analyzing device, and the initial setting values (such as, e.g., a calibration curve factor and a calibration factor) are changed by performing the corresponding maintenance.
However, in the case where it is desired to return back to the setting values before starting the corresponding maintenance so as to reset again due to reasons such as erroneously changing the setting values in the maintenance, only the initial setting data at the time of product shipment is available in the conventional exhaust gas analyzing device, and therefore such a resetting operation cannot be performed.
In addition, although the initial setting data at the time of product shipment can be restored by reading the initial setting data stored in the external recording medium appended to the exhaust gas analyzing device, the work thereof is complicated and in the case where the state before starting the maintenance is different from the initial state, it is not possible yet to return back to a desired state. In particular, in the case where other analyzers are added after product shipment, the setting values set in relation to the added other analyzers disappear only by returning back to the initial state, and it may be likely inexpedient to return back to the initial setting values in some cases.